
public class FiboRec{

	public static long fibo(int n){
		if(n < 1)
			throw new IllegalArgumentException("n must be >= 0");
		if(n >=1 && n <= 2)
			return 1;
		return fibo(n-1) + fibo(n-2);
	}

	
	public static void main(String[] args){
		System.out.println(fibo(Integer.parseInt(args[0])));
	}

}